The man says he got the idea from seeing a Livermore man on TV earlier this month exercising his right to carry an unloaded weapon.
It's legal in California, as long as it's not near a school.
So Wednesday, the Redwood City man walked into the Mi Pueblo Market, with a handgun on his hip.
The store manager called police. They determined he didn't break any laws, but the store exercised its right to make him leave.